Page 179 - Handbook of Structural Steel Connection Design and Details

Design of Connections for Axial, Moment, and Shear Forces

164 Chapter Two

This expression can be inverted to a form usable in the prying action
equations as
V
r 5 1.13T a1 2 b # r t
t
b
r v
For the present problem
4.125
r 5 1.13 3 28a1 2 b 5 17.8 kips , 29.8 kips
t
9.41
Use r 17.8 kips. Since T 39/8 4.875 kips 17.8 kips, the bolts
t
are ok for tension/shear interaction exclusive of prying action. Now,
checking prying action, which includes the bending of the angle legs,

4.44 3 17.8 3 2.08
t 5 5 0.993
C
B 2.875 3 58
1 0.993 2
r 5 ca b 2 1d 5 9.55
0.72 3 2.15 0.25
Since > 1, use 1, and
0.25 2
T 17.8a b s1.72d 5 1.94 kips , 4.875 kips, no good
d 0.993
1
Thus, the / 4-in angle legs fail. Try a 1/2-in washer plate. Then
0.5 2
5 1 1 a b 5 5.00
0.25
1 0.993 2
r 5 ca b 2 1d 5 1.91
0.72 3 5.00 3 2.15 0.25
Since > 1 use 1

0.25 2
T 17.8a b s1 1 0.72 3 5.00d 5 5.19 kips . 4.875 kips, ok
d 0.993
Therefore, the 1/2-in washer plates enable the connection to carry
5.19 8 41.5 kips > 39 kips, ok.
If ductility is a consideration, the ductility formula can be generalized to
b
F y ~ 2
d 5 0.163t2 ~ a 1 2b
b min 2
B b L
~ 9 13
With b 5 GOL 2 k 5 2 2 5 1.75
16 16
36 1.75 2
5 0.163 3 0.2525.00 a 12b 5 0.588 in , 0 .75 in, ok
B1.75 11.5
d b min 2

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